1. Field of the invention
The present invention concerns connectors for electrical cables comprising at least two jaw members made from a hard insulative material such as polyamide 6 charged 50% with glass fibers so that they are rigid, adapted to define at least two parallel channels between them, one per electrical cable, at least one metal contact member, preferably of aluminum alloy or tinned brass, carried by one of said jaw members, at least partly contained within a housing in the latter and having active parts at the front forming perforating teeth intercepting both of said channels to establish a bridge connection between the electrical cables, and clamping means adapted to move the jaw members towards each other to close said channels onto said electrical cables.
It is more particularly directed to the case where insulative material seals are provided on the active parts of the contact member (or each contact member where a plurality of contact members are employed), to be more precise soft insulative material (i.e. flexible and elastic thermoplastic material) seals surrounding or substantially surrounding said active parts to protect them more reliably from moisture when they are fitted to the electrical cables.
This is the case in the disclosures of French patent No. 2 601 516, which is a patent of addition to an earlier French patent application (84 09384) which has an equivalent U.S. Pat. No. (4,643,512), and French patent No. 2 634 070.
In the first of these documents the two seals for the active parts of the same contact member are joined together by a crosspiece.
They are portions of an inverted gusset sealing part which caps the exterior part of the contact member with which it is engaged in the respective housing of the respective jaw member, with sealing beads around the perforating teeth of this contact member.
However carefully it may be fitted, in practise this sealing part is not finally located until the connector is first clamped to the electrical cables.
In the second document the seals are overmolded continuously with a skin covering virtually all of the surface of the contact member.
In another connector currently marketed by the assignees of this application the contact members are simple blade members force-fitted into "ad hoc" grooves in the insulative jaw or jaws, after which a soft and durably elastic synthetic material is injected into all of the empty spaces between the blade members and the jaw members, such injection simultaneously producing sealing beads all around the perforating teeth, as claimed, described and/or shown in the aforementioned prior art documents, of which the assignee of this application is the proprietor.
In this latter product, in the "inverted gusset" solution of French patent 2 601 516 and in French patent 2 634 070, although an effective seal is provided between the perforating teeth and the cables to be connected by the sealing beads around said perforating teeth when the connector is clamped onto the cables, the sealing is less effective during such clamping between the crosspiece joining the beads and the contact member and between the latter and the groove for receiving it in the clamping jaw member. This is because of the restricted clamping upon assembly in the factory and also because the clamping is not applied directly to the crosspiece or the beads.
An object of the present invention is to improve sealing by hot deforming said crosspiece under pressure in the factory to deform it into contact with ribs which are in one piece with the insulative jaw member. Initially vertical, these ribs are heated and bent under pressure to a position at 90.degree. to their initial position, becoming embedded in the crosspiece and applying thereto an elastic compressive force producing a perfect seal between the crosspiece and the contact member and between the crosspiece and the insulative jaw member. This is achieved at the factory and is independent of the clamping of the connector when it is fitted to the cables to be connected.
Note that this new method constitutes an improvement on the solutions disclosed in the patents or patents of addition of the assignee of this application and may be applied to the latter solutions subject to modifications of the clamping jaw members in the manner described in this application.